The
Com_shutdown
status variable tracks the number of
SHUTDOWN statements. Because
status variables are initialized for each server startup and do
not persist across restarts, Com_shutdown
normally has a value of zero, but can be nonzero if
SHUTDOWN statements were executed
but failed.

Another way to stop the server is to send it a
SIGTERM signal, which can be done by
root or the account that owns the server
process. SIGTERM enables server shutdown to
be performed without having to connect to the server. See
Section 4.10, “Unix Signal Handling in MySQL”.